In communication networks, intelligence relates to the ability to have access to stored data, to process it and to make decisions on the basis of the data. Even the present communication networks, such as public switched telephone networks (PSTN), are to some extent intelligent, because they are able to process stored data in relation with, for example, routing of calls. A typical "intelligent" facility in modern communication networks is a conditional call forwarding which requires an analysis of the call situation and routing the call forward on the basis of the stored service profile of the call forwarding. Such intelligent facilities have, however, been an integral part of the basic network, and have thus required, for example, software updating in all the network exchanges in cases of altering or increasing the number of facilities.
An Intelligent Network (IN) is a network architecture which can be incorporated in the basic network, and which makes implementation and controlling of services faster, easier and more flexible. This can be achieved by moving the service control out from the switching exchange into a separate functional unit of the intelligent network. This is how the services can be made independent of the operation of the basic network, and changes in the structure of the basic network or in the software are not required in conjunction with altering or increasing the number of services. In addition to the actual network operator, the intelligent network may contain several service providers.
In fixed networks, standardization of intelligent networks has been rapid in recent years. Standards of intelligent networks include the CCITT Q.1290 and prETS 300 374-1, Intelligent Network Capability Set 1 (CS1). These standards define a specific functional and hierarchical model for the intelligent network. In this model, service control is transferred from the exchange of the basic network to a service control point (SCP) in the intelligent network. The SCP comprises a database and service logic programs (SLP), i.e. computer programs which fulfil the logic structure of a specific programs (service logic). The intelligent network services are created, tested and withdrawn by means of special equipment referred to as service creation environment (SCE). Service management function (SMF) is used for management of subscriber and network information in the database, including service specific information and service programs. The service switching point (SSP) is an exchange, for example that of the basic network, fulfilling the service switching function (SSF), in other words, the recognition of the intelligent network service and activation of interaction with the service control point SCP.
For recognition and activation of an intelligent network service, the intelligent network contains predefined triggers for the service, the triggers defining triggering criteria used for activation of the intelligent network service. The triggering criteria comprise, for example, the phase of the call routing, detection point (DP) according to the ETSI CS1 call model, which detection point is an event relating to call processing. If the triggering criteria defined by the trigger are fulfilled, the intelligent network service is activated in a SCP defined by the trigger.
As stated above, the intelligent network standards have been developed for fixed communication networks. There is no similar standardization for mobile communication networks. It is difficult to implement intelligent network functionality of the ETSI CS1 type, for example, in a mobile communication network in which mobile subscribers have no fixed access point in the network. However, in every part of the mobile communication network it should be possible to recognize mobile subscribers using intelligent network services, have information on the services and triggers of each mobile subscriber, etc. This easily leads to massive data files and/or large data transmission requirements within the mobile communication network.